Milling-cutter



' (No Model.)

S. BROADBENT.

' MILLING GUTTER.

Patented Feb. 26', 1884.

" STATES Armar Nil LLllNG-C'UTTER.

SPECIFICATION forming part` of Letters PatentV No. 294,192, dated February 26, 1884.

i Application lilel August-20, 1883. (No model.)

i" 0 all whom, it may concern.-

Be it known that I, SIDNEY BROADBENT, of Scranton, in the county of Lackawanna and State of Pennsylvania, have invented a new and'useful Improvement in Milling-Tools; and the following is declared to be a description of the same.4 l

Milling-tools are employed for removing surplus portions of -metal in the construction of machinery, and especially are they used for cutting the teeth of gear-wheels. These milling-tools are revolved by suitable machinery,

and in the act of cutting or smoothing the teeth the tool is moved across the face of the wheel.

Heretofore it has beenl usual to employ planing or sl'otting machines to rough out the teeth of large gears, and then finish witha iiuted milling-tool of proper shape. Millingtools to cut and partly rough have been employed; but these left ribs which had to be chipped out. These millingtools and their teeth or cutting-edges "have generally been formed outjof one piece of metal. The teeth upon these milling-tools are usually parallel with the axis of the tool, the tool for roughing out being made with .annular grooves,with teeth in the intermediate rings, and the finishing-tool having teeth the whole length ofthe cutting-surface. I

My invention has for its object a millingtool that will not vibrate or chatter when in use, and which will produce a smooth surface. In this tool a line drawn through the cuttingedgesof the teeth will be at an angle to the axis of the tool, thereby giving the teeth a shearing out; and my invention hasV further for its object the forming of teeth in millingy tools in rings or sections, so that the teeth shall alternate with each other, but they will act upon the whole of the surface that is to be milled Without having any iin or unfinished part uponl the surface. These alternating teeth may, however, be made solid with the millingtool; or they maybe let into the surface of the' f said milling-tool either in a dovetailed slot or be secured by shanks driven into'hclesin said tool-stock. This form of milling-tool has been called a staggered milling-tool.77 In the drawings, Figure 1 is a longitudina section of my improved milling-tool. Fig. 2

. tool.

is a cross-section of the stock, with one ring in elevation. Fig. 3 is an elevation and partial'section ofa milling-tool wherein the teeth are made solid with the tool-stock. Fig. 4 is an end view of the tool shown in Fig. 3, and Figs. 5 and 6 are sections showing the teeth and the devices for holding them.

In Fig.- 1 a'is the spindle of the millingb is a key in a slot in said tool, and c is a tie-bolt passing 'through the spindle, for securing the tooth-rings in place. The toothrings d efg h i 'k have eacha 'central opening for the `spindle a, and a slot in their inner circumference for `the key b. The outer circum- .ference of each ring is made with teeth Z, having cutting-edges inclined at an angle to the axis of the milling-tool. The cutting-teeth on ring dare made with curved edges, to finish out the metal at the basis of the gear-teeth, and also the surface of the wheelbetween the teeth. The rings d ef g h ik andthe teethZ upon their surfaces are of any desired size for dressing the surfaces of the gear-teeth, and the slots or seatsl for the key b are cut in such positions that when the rings are threaded upon the spindle the teeth Z. ofone ring will` alternate with lthose of the next ring. The head of the tie-bolt c takes a bearing against the annular end l of ring d, and the nut c tightens such bolt and causes the head to clamp the rings securely in place. The key b prevents the toothed rings-fromturning when in use. One side or surface of each of the aforesaid toothed rings is turned o about one thirty-second of an inch deep and inside of the basis of the projecting teeth. This is done so spindle their faces shall come firmly together, and the edges of each set of teeth shall overlap upon the next ring, so that there will not be any iin or ridge in the surfaces of the nished gear-teeth, the edgesV of one range of cutters overlapping the path described by the next edge of cutters, so as to make a smooth finish in the metallic surface;

l In Figs. 3 and ft the teeth l are represented as alternating in position, andA theteeth as wider than the space between one tooth and the next. The cutting-edges are inclined to the axis of the spindle, similar to those in the milling-tool shown and described with referthat when the rings are put together upon the Q eenmaaence to Figs. 1 and 2; but in Figs. 3 and 4 the teeth are shown as solid with the spindle. These teeth Z, instead of being made solid with the spindle, or formed npon rings threaded upon a spindle, niay be made, as shown in Fig. 5, with shanks let into dovetailed slots in the spindle, or with cylindrical shanks, and driven into holes in the spindle, as in Figli.

A milling-tool made in the form described, having teeth placed alternately with inclined cutting-edges, and with the teeth wider than the spaces between the ranges of teeth,vis the main feature of my invention. This form 0f milling-tool can be used alone to do the work formerly accomplished by both the roughing and iinishing tools, as it is capable of cutting or smoothing the teeth at one operation.

I claim as my inventionl. A milling-tool composed of disks or rings with teeth upon their edges, each tooth being longer on its edge than the thickness ofA the disk, and said disks secured together upon a spindle, With the teeth on one disk between the teeth upon the next disk, substantially as set forth.

2. The combination, in a milling-tool, of the spindle a, key b, and tie-bolt ,0, with movable rings, each of which is provided with teeth that are Wider than the thickness of the ring,

`andai; an inclination, as specified.

3. The milling-tool having peripheial teeth in rows, the teeth in one row alternating with those in the next, andthe edge of each tooth being at an inclination vand longer than the distance between one tooth and the next, suby stantially as set forth.

Signed by me this 14th day of August, A. D. 1883.

SIDNEY BROADBENT. "Witnesses:

J. M.POORE, E. F. BOYLE. 

